The paper addresses the question of whether matching a persuasive message to a recipient's self-concept can enhance message processing. A large body of experiments within the Elaboration likelihood model proved that framing a message so as to be perceived as selfrelevant led to more careful argument scrutiny. In this research, we matched the messages with previously assessed need for cognition - tendency to engage in and enjoy effortful cognitive tasks. Two possible sources of motivation to process a persuasive message were hereby confronted: dispositional (cognitive style) and situational (matching). Results showed a significant attitude change, but the main hypothesis was not confirmed: matched messages did not produce more argument processing activity than the mismatched. Manipulations did not have any significant effects on message processing of the high need for cognition participants. Contrary to expectations, participants low in their need for cognition elaborated the message more carefully when it was mismatched, that is when the message addressed them as persons inclined to careful thinking. Results can be explained within the framework of self-affirmation theory, which argues that providing people with an opportunity to affirm their sense of selfworth makes them more open to persuasion attempts, as well as more objective. Results are discussed from a wider theoretical and empirical perspective of motivation.